The influence of diabetes mellitus on acute renal damage following coronary artery bypass graft surgery

Background: DM is a known risk factor for developing postoperative acute kidney injury (AKI) after Coronary Artery Bypass Grafting (CABG). Postoperative AKI is associated with increased short- and long-term morbidity and mortality. This study aims to comprehensively evaluate the impact of diabetes mellitus on the occurrence and severity of AKI following CABG. Methods: This comparative cross-sectional study was carried out in the department of cardiac surgery, national institute of cardiovascular diseases (NICVD) on a total of 60 patients undergoing CABG. Postoperative serum creatinine was measured at 24 hours, 48 hours and 72 hours after surgery. Group A included 30 patients who were diabetic and Group B included 30 patients who were non-diabetic. Statistical analysis was performed using statistical package for social sciences (SPSS). A p value<0.05 was considered statistically significant. Results: During the observation period overall, 16 (26.67%) out of 60 patients developed postoperative AKI with varying severity. Among them, 12 patients were from diabetic group and only 4 patients belonged to non-diabetic group (40% vs. 13.33%, p<0.020). Consequently, duration of ICU stays (7.87±4.98.12 vs 4.13±2.65 days, p<0.001) and length of postoperative hospital stay (7.88±2.92 vs 13.0±4.95 days, p<0.001) were also found to be significantly prolonged in group A patients. Conclusion: The present study revealed that patients with diabetes mellitus were more susceptible to develop post CABG AKI in spite of having no pre-existing renal impairment.